Security Device, Method and System For Financial Transactions, Based on the Identification of an Individual Using a Biometric Profile and a Smart Card

ABSTRACT

A device to secure payments or transactions made with a smart card and validate the identity of the smart card holder using a client/server biometric control operation, regardless of whether the payments or transactions are made directly at a point of sale or indirectly. A client/server-type system authenticates the identity of a smart card holder, based on the use of the smart card and on the identification of the holder by biometric data which are stored on an extended memory smart card and compared with biometric data from an external, remote database that is secured and operated by the third-party authentication server or by the financial institution, but which, for reasons of security and performance, are not transferred over the telecommunication network.

The present invention relates to an innovative device for securing payments or transactions made with a smart card, and for validating the identity of the smart card holder using a client/server biometric control operation, regardless of whether these payments or transactions are made directly at the point of sale or from a PC (personal computer or shared open-access computer) connected to the Internet, or using a cell phone, a portable computer (also known as a laptop), a PDA (Personal Digital Assistant), or any other computer or mobile or fixed means that can connect via any telecommunication network and carry out a transaction involving biometrics from the point generating said transaction. The present invention also relates to smart-card-holding employees of financial institutions who perform professional inter-bank transfers. This invention can also be used for electronic funds transfers between countries, between groups of countries, between groups of countries and countries and between international organizations and countries.

The present invention is designed in the form of a client/server-type system for authenticating the identity of a smart card holder, dually based on the use of the smart card and, on the identification of the holder by means of biometric data stored on an extended memory smart card, by comparison with biometric data from an external, remote database that is secured and operated by the authentication third party or by the financial institution, however, where biometric data, for reasons of security and performance, are not transferred over the telecommunication network.

Nowadays, around the world, payments or transactions are normally made using a magnetic-stripe card, with the transaction slip that is issued requiring a signature as art of the act of purchasing. In some countries, the signature is replaced by a multiple-digit PIN code, which is compared with that resident in the smart card memory.

Given the very strong volume in growth worldwide of purchase transactions or financial transfers, involving cards with or without microprocessors as the medium, more and more payments or transactions can be subject to fraud, having some transactions not requiring a PIN code. Although the PIN code ensures better security than the signature alone on the purchase slip, it risks being cloned or stolen from its owner.

Also, at present, card holders, regardless of whether the cards are smart or not, are identified by their personal proof of identification (personal ID); it has been observed that numerous card frauds, whether the card is smart or otherwise, occur with the issue of multiple cards by different financial institutions to a single individual, without it being possible to correlate and verify his identity in the form in which it is supplied today to the issuing financial institutions. Among other things, these frauds are due to the use of false papers, identity cloning in all its forms, or even the simple physical theft of cards, smart or otherwise, blank or already assigned.

The device according to the invention makes it possible to remedy these drawbacks and these frauds, by providing financial institutions with a reinforced and inviolable securing method for transactions performed using a smart card.

Nowadays, these devices are made possible by the increase in the memory size of the smart cards which has risen from a level of below 100 Kb to a level of above 512 Kb. This significant increase in the memory size of the smart cards will make it possible to include stored information or software developed in the Java® (Sun) or .net® (Microsoft) environment, or with any other available language within the cards' memory.

Furthermore, the provision of cards capable of being used on both a low-bit rate connection port—as used today—and on a compatible fast high-bit rate port, means that fast real-time interchanges can be conducted on these smart cards, and software, or stored information, can be read at high speed. The availability of the two telecommunication ports on the microprocessor will allow for the complete and gradual migration of the installed base of payment terminals without deadlocks or incompatibilities.

This available memory capacity will enable us, to both store graphical information with a high enough level of precision to be perfectly usable and, to embed software keys and computation algorithms, as well as to toughen such algorithms, keeping in line with the capabilities offered by new developments. It will be noted that the current and common size of smart card memories, as well as the unavailability of a fast high-bit rate communication port, did not allow such a process in the past.

The global inventive device itself comprises a number of devices that are described below. These devices are numbered from X00100.

FIG. 1 represents the global inventive device.

1. Description of the Four Devices According to the Invention:

-   -   1.1 [X00100] Description of the First Device:

Storage Format for the Information on the Smart Card

This device according to the invention corresponds to the storage on the microprocessor of the personal smart card issued by the financial institution of one or more encrypted biometric data items that are supplied by the card holder, and that are associated with a convergence identifier according to the device [X00200]. The biometric data are encrypted before being stored in the microprocessor memory included in the smart card.

For any biometric imprint—fingertip, face, iris, retina, voice, or other—the software associated with the hardware (microcontroller associated with a flash memory, or equivalent device) will detect a group or series of critical points.

For reasons being more security-oriented than technical, the sensor will be programmed to select a greater or lesser number of points ranging from 5 to over 30. In practice, depending upon the computation power available in the terminal, which will evolve over time, and the time needed to perform the computations, and the transmission of the information resulting from these computations, the parameters will be modifiable. Each point will be described by coordinates on the sensor.

-   -   1.2 [X00200] Description of the Second Device: Device for         Informing the Biometric Database

This device is for informing the biometric database and comprises the system, according to the invention, of issuing or refusing to issue as a result of false identity, identity cloning or identity theft. The identity check is based on the creation of two files.

The first file contains a sequence of the following type: convergence number, name, first name, national identity number, date of birth, banking institution, branch number, account number, and any other information needed in order to correctly use financial and banking services. Upon creation, the convergence identifier will be a temporary identifier, the final identifier being supplied only upon completion of the acknowledgement of the data validity by the authentication third party.

The second file contains a sequence of the following type: convergence number linked to the biometric information stored on the biometric database of the remote servers of the authentication third party.

For security reasons, a master server comprising the second file, that of the authentication third party, will be installed redundantly in the premises of the financial institution, and then can be used should the remote servers temporarily fail.

The authentication third party will have only an extract from the first file, in other words the convergence number, name, first name, national identity number, date of birth, banking institution, branch number. The account number will not be stored on the remote servers of the authentication third party.

FIGS. 2 and 3 show the second device [X00200], or the device for informing the biometric database.

-   -   1.3 [X00300] Description of the Third Device: Device for         Transfering the Biometric Data stored by the financial         institutions to the remote servers of the authentication third         party.

The device according to the invention represents, for each individual requesting or holding a smart card, biometric data and personal identity data (name, first name, date of birth, etc.), collected by the financial institution, the transmission and the duplication on the server of the authentication third party or the remote servers. These data are transferred by the financial institution to the remote servers, and comprise a temporary identifier number generated by the software supplied by the authentication third party to the financial institution.

Once the data is stored, the device according to the invention performs a comparative analysis of the data supplied with the data existing on the database of the remote servers of the authentication third party, provided that these data already exist. A correlation will then be performed between the personal and biometric data in order to inform the financial institution as to the authentication of the individual.

If an individual already exists with similar biometric data but different personal identity, the authentication will be rejected and flagged to the financial institution. In return, the financial institution will receive the temporary identifier associated with a rejection code. This rejection code will immediately be interpreted by the software supplied by the authentication third party to the financial institution, and will recommend not issuing the card for reasons of identity cloning.

In the case where the individual is not already represented by his biometric and personal data on the remote servers of the authentication third party, his identity will be registered as valid. An identifier number will be generated. This identifier will be called convergence identifier. The temporary identifier issued by the financial institution will then be associated with the convergence identifier, and these two types of identifiers will be forwarded simultaneously to the requesting financial institution. The transmission of this data to the financial institution server will confirm the authentication of the individual for the issue of the smart card.

It will be noted that any one individual can have several different convergence identifiers, if he has requested bank cards from several different financial institutions, but can have only one convergence identifier for each financial institution. It will also be noted that if an individual raises several simultaneous requests to obtain smart cards within the same banking network (the same financial institution), as of the second request, the temporary identifier number, associated with a code flagged and recognized as a multiple requester, will be issued and transferred to the financial institution, and the decision of whether to issue a card or not will rest with the financial institution.

Since the authentication third party offers its services to multiple financial institutions, the device according to the invention will offer a greater level of security once the quantity of information collected is exhaustive.

It should be stated that, for security and performance reasons, the device according to the invention does not provide for the actual transport of biometric data in itself.

FIGS. 4, 5 and 6 represent the third device [X00300], or device for transferring biometric data stored by the financial institutions to the remote servers of the authentication third party.

-   -   1.4 [X00400] Description of the Fourth Device:

Biometric authentication device: this concerns the client/server procedure for validating the identity of a smart card user at the time of a purchase, or of a transaction, at a point of sale or on the Internet, or even using any other type of wired or wireless (GSM, UMTS, Bluetooth, WiFi or other) telecommunication network, or even by cell phone, by personal computer (also known as laptop), by PDA (Personal Digital Assistant) or other computer, or even using any other mobile or fixed equipment that can be connected via any telecommunication network, and perform a transaction involving biometrics from the point generating said transaction.

-   -   -   1.4.1 Innovative principle of biometric payment by smart             card, at the time of a purchase or of a transaction, at a             point of sale or on the Internet, or even using any other             wired or wireless (GSM, UMTS, Bluetooth, WiFi, or other)             telecommunication network, or even by cell phone, by             portable computer (also known as laptop), by PDA (Personal             Digital Assistant) or other computer, or even using any             other mobile or fixed equipment that can be connected via             any telecommunication network, and perform a transaction             involving biometrics from the point generating said             transaction.

The payment, or the transaction, is performed by using a smart card payment terminal at the point of sale, having, both, a local connection with a biometric imprint sensor, as well as, a microcontroller including/using a flash memory, or any other equivalent device, incorporated in the terminal. This microcontroller associated with a flash memory, or any other equivalent device, includes the original version of the software—integral part of the inventive device—which will perform the comparison computation against the selection of randomly chosen points, as described in the first device [X00100].

Modalities of the software/microcontroller associated with flash memory process, or any other equivalent device:

-   -   I Capture of the biometric imprint,     -   II Reading of the identifiers,     -   III Sampling of the notable points, chosen randomly,     -   IV Algorithmic computation/calculation,     -   V Encryption of the results, sending the encrypted computation         results and convergence identifier, the latter being associated         with payment or transaction request, to the financial         institution.         -   1.4.2 Software and Hardware Deployment:

A microcontroller associated with a flash memory, or any other equivalent device, containing the software image described above, will be incorporated in the point-of-sale terminal. It will be provided with an extended memory smart card reader, connected to a USB, or IEEE1394, or other equivalent type fast port, for the users wishing to make a payment or to conduct a transaction via a telecommunication network, of Internet or other type. Similarly, a software image could be incorporated in the personal computer or PC, in the cell phone, in the portable computer (also called laptop), in the PDA (Personal Digital Assistant) or other computer, or in any other mobile or fixed equipment that can be connected via any telecommunication network, and perform a transaction involving biometrics from the point generating said transaction, or even in any other tool using connectivity via a remote network and incorporating a biometric sensor, a computer, and a memory making it possible to store said software (volatile or non-volatile memory).

The algorithm will be supplied on a physical medium of CD or DVD Rom type, or downloadable, so that the user of a remote system can load it onto his machine.

Updates will be distributed at variable frequencies in order to be able to generate different algorithms, offering different computation results; these variants enable the manager of the identifiers to guarantee a very high level of security and quality concerning the validation of the identity of the people using this system.

In the same way, whether on the point-of-sale terminal or on the connected remote personal computer, or on any other connected device, the software version installed and available on each machine will be verified. On the point-of-sale terminal, or on the personal computer version, or even on any other connected device, a decision may be taken to perform a download to enable another authentication computation, if the version used at the time of the last preceding transaction is/becomes obsolete.

The personal computer or PC, the cell phone, the portable computer (also called laptop), the PDA (Personal Digital Assistant) or other device, or any other mobile or fixed equipment that can be connected by means of any telecommunication network, and capable of performing a transaction whereby biometrics is involved from the point generating said transaction, or any other device using connectivity via a remote network and incorporating a computer, and a memory enabling said software to be stored (volatile or non-volatile memory), must include one or more biometric sensors, either integrated or connected as peripheral devices.

-   -   1.4.3 Method and Architecture Concerning the Authentication of         the Smart Card Holder:

At the point of sale, at the time of a purchase, a consumer will present his smart card, and he will be asked to place, for example, his fingertip on a biometric sensor.

The inventive device—based on a client/server architecture comprising hardware—a microcontroller associated with a flash memory or equivalent device—biometric sensors (fingertip, face, iris, retina, voice or other imprint) and original software programmed and stored on the smart card—takes charge of identifying the smart card holder.

The inventive device functions on a single-request architecture, comprising two parts, the first, a transaction request addressed to the financial institution, and the second, an identity validation request addressed to the servers of the authentication third party or the financial institution.

-   -   1.4.3.1. First Part of the Device [X00400]:

The device [X00400] according to the invention performs a correlation, in local mode, between the encrypted data stored on the smart card's microprocessor and described in the first device [X00100], and the biometric data collected from the smart card holder. This is possible using original software developed according to the invention and incorporated in a microcontroller associated with a flash memory, or any other equivalent device, which is inserted into the terminal supporting the transaction.

The software and the microcontroller associated with a flash memory, or any other equivalent device, will incorporate management of the translation of the orthonormal matrix, in order to avoid the pitfalls of positioning on the sensor (it is possible, for example, to orient the fingertip a few degrees to the right or to the left relative to the theoretical axis of the sensor).

The positions of the points relative to the frame of reference (sensor matrix) and the relative positions of the points between themselves, as well as their vector orientation, will be the subject of an analysis which, initially, will be compared with the same computation as that which is available on the smart card itself.

This comparison will show an immediate correlation or its absence with the living imprint.

It will be noted that the imprint sensor will be of the thermometric or other type, in order to verify whether the subject is living or not, and that it is not an image copy of said imprint. The other sensor types will include an infra-red or other type verification, checking the temperature of the subject.

-   -   1.4.3.2. Second Part of the Device [X00400]:

The inventive device [X00400] performs a correlation between the encrypted data described in the device [X00200], and the encrypted data resident on the remote servers of the authentication third party, using a local computation, the results of which are forwarded to the remote servers of the authentication third party, or of the financial institution, which performs the same computations and analyzes their results again. These results are accompanied by the encrypted convergence identifier, and the part of Java® (Sun) or .net® (Microsoft) code, or of any other available language, stored on the smart card, as well as information relating to the transaction itself.

The convergence identifier, the local computation results, the part of Java® (Sun) or .net® (Microsoft) code, or of any other available language, are forwarded in a single request, by the terminal, to the financial institution, which itself forwards to the authentication third party, or to the financial institution, the convergence identifier, the local computation results, the part of Java® (Sun) or .net® (Microsoft) code, or of any other available language, for an identity check.

While the results are being prepared by the authentication third party, the financial institution performs its own financial checks on the account of the smart card holder, pending acceptance or rejection of the identity of the smart card holder by the authentication third party, or by the financial institution itself. Once the acceptance or rejection of the identity of the smart card holder has been pronounced by the authentication third party, the financial institution terminates the transaction.

The identity checking operations are performed in real time.

The procedure will be strictly identical if the purchase is made via the Internet, or by any other means, or even via any other wired or wireless (GSM, UMTS, Bluetooth, WiFi or other) telecommunication network, or even by cell phone, by personal computer (also known as laptop), by PDA (Personal Digital Assistant) or other computer, or using any other mobile or fixed equipment that can be connected via any telecommunication network, and perform a transaction involving biometrics from the point generating said transaction.

FIGS. 7 and 8 represent the fourth device [X00400], or client/server device for validating the identity of a smart card user at the time of a purchase at a point of sale or on the Internet, or even via any other wired or wireless (GSM, UMTS, Bluetooth, WiFi or other) telecommunication network, or even by cell phone, by portable computer (also known as laptop), by PDA (Personal Digital Assistant) or other computer, or using any other mobile or fixed equipment that can be connected via any telecommunication network, and perform a transaction involving biometrics from the point generating said transaction.

-   -   2. [X00500]: Description for each Step of the Authentication         Device According to the Invention, and Described Previously.

Step 1: The financial institution receives a request to issue a smart card from a holder.

Step 2: The financial institution asks the future smart card holder to submit to having his biometric imprints captured.

Step 3: The biometric imprints are stored on the server of the bank branch, then transferred to the central server of the financial institution, with the data present on the branch server being deleted for security reasons.

Step 4: The biometric imprints are stored on the remote servers of the authentication third party.

Step 5: The financial institution asks for the identity to be validated by sending a request to the remote servers of the authentication third party.

Step 6: The preceding request is accepted, with no similar biometric imprint previously having been filed by the person requesting the issue of a smart card.

Step 7: The financial institution decides to issue the card in the name of the requesting person, and the biometric imprint or imprints supplied, the convergence identifier, the results of the local computation, the part of Java® (Sun) or .net® (Microsoft) code, or of any other available language, are stored on the microcontroller associated with a flash memory, or any other equivalent device, included in the smart card.

Step 8: The smart card holder goes to a point of sale and wants to purchase goods equal to a value of 100 euros.

Step 9: The holder's smart card is inserted into the payment terminal, and the holder is asked to place his fingertip, or any other part of the body, on or facing the appropriate biometric sensor, depending on the part of the body requiring validation.

Step 10: In local mode, the payment terminal validates the consistency of the two imprints, that of the card and that of the sensor.

Step 11: Having locally validated the consistency of the two imprints (the one stored on the smart card and the one that is the living part of the body) the payment terminal sends, in remote mode, a single request comprising two parts, one addressed to the financial institution and the other addressed to the servers of the authentication third party, as described in [X00400].

Step 12: The authentication third party in turn validates the consistency of the biometric identity of the smart card holder, and of the biometric identity stored on its servers; it then sends, in return, an identity validation or rejection code to the financial institution.

Step 13: The financial institution authorizes or refuses authorization of the 100-euro transaction, according to financial solvency data, by sending a positive or negative instruction to the payment terminal (FIG. 11).

Similarly, the financial institution authorizes or refuses authorization of the 100-euro transaction, according to financial solvency data, by sending a positive or negative instruction to any one of the other types of terminals available on the market, such as the cell phone, the portable computer (also known as laptop), PDA (Personal Digital Assistant) or other, or any other mobile or fixed equipment that can be connected via any telecommunication network, and perform a transaction involving biometrics from the point generating said transaction (FIG. 12).

FIGS. 9, 10, 11 and 12 represent the device by steps [X00500]. 

1-9. (canceled)
 10. A system designed to provided biometric authentication of a smart card holder which performs an electronic transaction in which biometrics are involved from the point generating said transaction, said smart card holder being connected to a communication means and to a biometric payment terminal, or any other transactional terminal comprising a smart card reader, designed to receive dedicated software operating as a communication gateway to the remote servers of the authentication third party, and comprising a link to one or more biometric sensors, incorporated or not in the terminal, which is connected to a computer linked to said communication means, the system is characterized in that it comprises: a first device (X00100) suitable for storing on the microprocessor of the personal smart card delivered by a financial institution, one or more encrypted biometric data items supplied by the card holder, and associated with a convergence identifier obtained from a second device, the biometric data, are of a morphological nature—fingertip, face, iris, retina, voice or other imprints, being encrypted before storage in the microprocessor memory included in the smart card; a second device (X00200) suitable for receiving the biometric data from the first device, and computing a convergence identifier associated with these biometric data and the convergence identifier to the remote server, and suitable for informing the biometric database of the remote server, and suitable for checking the identity using files, from both a file obtained from taking biometric imprints in real time (mobile or fixed payment terminals or personal computer or computer server) as well as from a central database containing, for each individual, a stable master file on remote server containing the source convergence identifiers that can be used to perform the correlation of the identities by comparison of the two files; a third device (X00300) suitable for receiving the biometric data from the sensors of the payment or identification terminals, data intended to inform the central database, and suitable for computing a temporary convergence identifier based on these data, and suitable for transferring the biometric data stored by the financial institutions or the identification centers to the remote servers of the authentication third party, these data comprising for each of the transactions, a temporary convergence identifier, generated by the software supplied by the authentication third party to the financial institution or to the identification center; and a fourth device (X00400) suitable for encrypting the biometric data and the convergence identifier and used for biometric authentication, and suitable for performing a correlation and comparison between the data of the files obtained from taking biometric imprints in real time (mobile or fixed payment server) and encrypted, and the encrypted data resident on the remote servers of the authentication third party—in other words, the stable master file of each individual, via a local computation, the results of which are forwarded to the remote servers of the authentication third party, or of the financial institution or of the identification center, which performs the same computations and reanalyzes their results, these results are accompanied by the encrypted convergence identifier, and by the part of Java® (Sun) or .net® (Microsoft) code, or of any other available language, stored on the smart card, as well as information relating to the transaction itself.
 11. The system as claimed in claim 10 is characterized in that the smart card reading terminal can be a mobile, personal and portable terminal, in which the means of communication with the remote authentication server is the Internet network, or any other wired or wireless (GSM, UMTS, Bluetooth, WiFi or other) telecommunication network, the smart card reading terminal can be a cell phone, a portable computer (also known as a portable PC or laptop), a PDA (Personal Digital Assistant) or other computer, or even any other mobile or fixed device, that can be connected via any telecommunication network.
 12. The system as claimed in claim 10 is characterized in that the physical medium of the invention is both the smart card, as well as a remote authentication server, the smart card holder can be any individual authorized by a financial institution to use a smart card as a personal payment means, or even an employee authorized by said financial institution performing an inter-bank transfer or a transaction in the course of his professional business, or even an employee of the civil service or of an international organization performing electronic funds transfers between countries, between groups of countries, between groups of countries and countries and between international organizations and countries.
 13. The system as claimed in claim 10 is characterized in that said dedicated software can be modified or parameterized in time, by successive changes, and/or by parameterizing, in order to avoid piracy and defrauding of the computation results.
 14. The system as claimed in claim 10 characterized in that only the authentication third party, or the financial institution, knows the programming of the embedded and remotely-operable software, and can recognize the validity of said computations as a function of the time; several versions of the software will be deployed and installed in the network, and the series of the terminals holding an identified version of the software will be recorded in the database of the authentication third party, or of the financial institution.
 15. The system as claimed in claim 10 is characterized in that the first tile contains a sequence of the type: convergence number (also called convergence identifier), name, first name, national identity number, date of birth, bank, branch number, account number, and any other information necessary to the correct operation of the financial and banking services, on creation, the convergence identifier will be a temporary identifier, the final identifier being supplied only on completion of the acknowledgement of the validity of the data by the authentication third party.
 16. The system as claimed in claim 10 is characterized in that the second file contains a sequence of the type convergence number (also called convergence identifier) linked to the biometric information stored on the biometric database of the remote servers of the authentication third party.
 17. A biometric authentication method designed to be implemented by a device as claimed in claim 10, is characterized in that it comprises steps of: according to a device (X00100), establishing biometric identification criteria for a smart card holder in order to prepare the storage format. According to a device (X00200), storing biometric data of an individual in the memory of the smart card (or even the smart card) according to a device [X00100]; constructing/compiling a database of convergence identifiers computed from biometric data, for each card holder, according to a device (X00200); the assignment of a convergence identifier computed and associated with any biometric data item in the first file stored on the smart card, this first file containing bank data concerning the holder, his biometric data, and the computed convergence data identifier, enabling the data to point towards each other in order to obtain extremely short response times, independently of the size of the database, these data are transferred, so that they can be compared to the master file (second file), in real time, after transfer using a communication network to the systems of an authentication third party, correlated by the convergence identifier, identical to the one stored on the smart card, this master file (second file) contains only biometric data and the convergence identifier computed on the server according to the same algorithm as on the smart card at the time of manufacture of the smart card, the comparison between the biometric data of the first and the second files, converged using the convergence identifier, guarantees or refutes, depending on the case, the strict equivalence of the data, the authentication third party validating or refusing the identity of the holder; transferring the biometric data of the individuals, stored by the financial institutions, to the remote servers of the authentication third party; generating a biometric authentication request according to a device, from a transactional terminal of any type, and operating on any type of network, wired terrestrial, optical, wireless terrestrial, satellite, hybrid, or another kind; carrying out a correlation between a file resulting from computations, transmitted by the transactional terminal, and the database of convergence identifiers, the latter being linked to biometric data; checking the authentication and searching for the biometric identity filing antecedents, not only for all the branches of a single financial institution and for all countries, but also for all the different financial institutions of the same country or of different countries; transmitting results of computations linked to biometric data corroborating the identity of an individual, and associated with a payment, or with a transaction; and transmitting an instruction in return according to a device [X00400], following on from the results of the authentication, to a financial institution, or other, in order that in turn the latter can authorize, or refuse, the transaction at the point of sale or on the Internet, or on any other communication network, or using another transactional means, this transaction can be a bank transaction, an inter-bank transaction (between financial institutions), or a transaction between countries, between groups of countries, between groups of countries and countries and between international organizations and countries and reciproquely.
 18. The biometric authentication method designed to be implemented by a device as claimed in claim 10, between a person holding or requesting a smart card, a financial institution and an authentication third party, characterized in that it comprises the following steps: the financial institution receives a request from a holder to issue a smart card; the financial institution asks the future smart 5 card holder to submit to having his biometric imprints captured; the financial institution stores the biometric imprints on the server of the bank branch, then, in a second stage, transfers them to the central server of the financial institution, with the data present on the branch server being deleted for security reasons; the authentication third party stores the biometric imprints on its own remote, secure and redundant servers, assigning them the convergence identifiers; the financial institution asks for the identity to be validated by sending a request to the remote servers of the authentication third party; the preceding request is accepted, no similar biometric imprint previously having been filed by the person requesting the issue of a smart card; the financial institution decides to issue the card in the name of the requesting person, and the biometric imprint or imprints supplied, the convergence Identifier, the results of the local computation, the part of Java® (Sun) or .net® (Microsoft) code, or of any other available language, are stored on the microcontroller associated with a flash memory, or any other equivalent device, included, in the smart card; the smart card holder goes to a point of sale and wants to purchase goods; the holder's smart card is inserted into the payment terminal, and the holder, is asked to place his finger, or any other part of the body (fingertip, face, iris, retina, voice or other imprint), on or facing the appropriate biometric sensor, depending on the part of the body that needs to be validated, this smart card can also be inserted into a biometric imprint card reader, being linked to a personal computer, in order to perform a transaction via the Internet, from the home, for example; in local mode, the payment terminal validates the consistency of the two imprints, that of the card and that of the sensor; having locally validated the consistency of the two imprints (the one stored on the, smart card and the one that is the living part of the body), the payment terminal sends, in remote mode, a single request comprising two parts, one being addressed to the financial institution and the other being addressed to the servers of the authentication third party; the authentication third party in turn validates the consistency of the biometric identity of the smart card holder and the biometric identity stored on his servers; it then sends, in return, an identity validation or rejection code to the financial institution; and the financial institution authorizes or refuses the transaction, according to the financial solvency data, by sending a positive or negative instruction to the payment terminal. 